Site symmetry

From Online Dictionary of Crystallography

Definition

The site-symmetry group (often called point symmetry) of a point is the finite group formed by the set of all symmetry operations of the space group of the crystal that leave that point invariant. It is isomorphic to a (proper or improper) subgroup of the point group to which the space group under consideration belongs. In general, the origin is a point of highest site symmetry.

See also

Sections 2.2.12 and 8.3.2 of International Tables of Crystallography, Volume A